Rapid Identification of Gram-Negative Bacteremia and Impact on Anti-Pseudomonal Antibiotic Consumption in Combination with Antibiotic Stewardship at a Community-Based Hospital System

BACKGROUND: Rapid diagnostics for blood cultures have shown to decrease unnecessary antibiotics; however, this has mostly been studied in gram-positive organisms. The Verigene Gram-Negative Blood Culture Test (BC-GN) identifies eight bacteria at species/genus level and six resistance genes, detected 2 hours from a positive blood culture. By identifying the gram-negative (GN) pathogen earlier compared with traditional methodology, there is the potential to decrease broad spectrum antibiotic utilization. The purpose of this study was to determine the impact of Verigene BC-GN with antibiotic stewardship on anti-pseudomonal (AP) antibiotic consumption in GN bacteremia among pathogens when AP therapy is not needed. Based on local susceptibility data, this included Escherichia coli, Klebsiella pneumoniae, Klebsiella oxytoca, and Proteus spp. METHODS: This multi-center, pre-post quasi-experimental study was conducted at the five hospitals that compose Scripps Healthcare. Verigene BC-GN results were communicated to pharmacists in real-time, who then notified physicians for antibiotic evaluation. Education was provided to pharmacists and physicians regarding implementation, and antibiotic selection recommendations were chosen based on site specific antibiogram data. A retrospective chart review was performed one year prior and five months post-implementation of Verigene BC-GN. Patients > 18 years old with bacteremia caused by E. coli, K. pneumoniae, K. oxytoca, or Proteus spp. within 48 hours of admission were included. The primary endpoint was AP vs. non-AP antibiotic days of therapy per day admitted (DOT/DA), within the first five days of admission. Secondary endpoints included hospital and ICU length of stay (LOS) and mortality. RESULTS: AP antibiotic consumption significantly decreased after implementation of Verigene BC-GN (0.45 vs. 0.32 DOT/DA, P < 0.001) while non-AP antibiotic consumption significantly increased (0.61 vs. 0.75 DOT/DA, P < 0.0001). Overall LOS was 7.0 vs. 6.2 days (P = 0.12) and in-house mortality was 7.0% and 4.3% (P = 0.18) pre and post-implementation, respectively. CONCLUSION: Verigene BC-GN, with antibiotic stewardship, successfully demonstrated a shift in antibiotic utilization away from broad-spectrum AP antibiotics, in infections where Pseudomonas coverage is not necessary. DISCLOSURES: All authors: No reported disclosures.